Despite the many varieties and sizes of shrimp, there are only subtle differences in flavor and texture between the species of this popular shellfish. So unless there's an aesthetic reason for choosing a particular size, all shrimp may be used interchangeably in recipes, with only minor adjustments in cooking times. Simple enough.
What often does cause confusion, however, is the terminology used in connection with this shellfish. Medium-sized varieties, termed shrimp in the United States, are referred to as prawns in other parts of the world.
Then there is the word scampi. It may used to describe any of several large prawns, small members of the lobster family having long claws, or a finished dish of shrimp sauteed with butter and garlic.
For our purposes, the term shrimp covers the gamut.
When selecting fresh shrimp, choose those that are dry, firm and have a sweet aroma. As this shellfish ages, it develops a chlorine odor.
One pound of raw--or green--shrimp in the shell should yield three servings. The same is true of a half pound of cooked shrimp without the shells. (Thus it takes 2 to 2 1/2 pounds of shrimp in the shell to yield about 1 pound--or two cups--of cooked, shelled shrimp.)
Depending on the size, a pound will have the following number of shrimp:
Very Tiny-- 72 to 100
Tiny-- 50 to 72
Small-- 25 to 50
Medium-- 20 to 25
Large-- 16 to 20
Jumbo-- 10 or less
Shrimp may be cleaned either raw or cooked. Cooking in the shells does, however, add flavor.
The heads and shells removed from raw shrimp may be discarded or used to prepare stock and soups. If desired, freeze and use later.
Most shrimp found in local supermarkets already have the heads removed. Should they still be attached, however, break the heads away from the bodies, leaving the tail meat intact.
Holding the shrimp with one hand, use the thumb and index finger of the other hand to remove and discard the legs (Step 1). The shell will then be easy to peel away, beginning on the underside at the head end of the body (Step 2). The tail may be removed, if desired.
Shrimp have an intestinal vein that runs down the outside curve of the body. In smaller shrimp removing this vein is optional, but in larger varieties the vein is typically an unattractive dark color and may contain grit that can interfere with the taste.
To remove the vein, make a cut about 1/8-inch deep down the outside curve of the shrimp with a sharp paring knife (Step 3). Use the point of the knife (Step 4) or the end of a wood pick to remove the vein, then rinse the shrimp under cold water and drain on paper towels.
To butterfly shrimp before cooking, peel away the shell, leaving the tail intact. Devein, then place the shrimp on its side and continue to slice almost through (Step 5). Turn and spread the shrimp to form a butterfly shape (Step 6).
All shrimp cook quickly, and overcooking tends to toughen this shellfish. Follow recipe directions, and keep in mind cooked shrimp should still be firm to the touch and opaque white tinged with pink.
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